The effects of micro-ramp height and location on a shock induced separation bubble were quantified using planar particle image velocimetry measurements. Conditional averaging was used to show that the amount of separation is related to the momentum flux in the near-wall region (< 0.5?) of the incoming boundary layer. The momentum flux added to this region scales linearly with micro-ramp height and larger microramps are shown to be more effective in stabilizing the interaction. Full boundary layer mixing is attained 5.? downstream of the micro-ramp and this forms a lower limit on the required distance between microramp and reflected shock foot.